1. Field of the Invention
The present invention relates to communication networks and, more particularly, to a method and apparatus for overlaying whispered audio onto a telephone call.
2. Description of the Related Art
Telephone networks have been in use for many years and have evolved considerably over time. The Public Switched Telephone Network (PSTN) is a circuit network that allows telephone calls to be placed between two or more parties. Voice traffic may also be carried on a packet network such as the Internet using a networking protocol commonly referred to as Voice over IP (VoIP). In addition, cellular and other wireless networks have been developed and deployed to allow users to place and receive telephone calls wirelessly. All of these networks, and other private telephone networks, are interconnected to allow individuals on different types of networks to make and receive telephone calls.
As telephone services are developed, they are deployed on the network so that the new services may be sold to telephone customers. For example, telephone conferencing has been developed which allows two or more parties to be interconnected by a bridge. The bridge senses which person is talking and causes that audio stream to be sent to the other participants to the conference call. The bridge may also interject audible information by interrupting the speaker. For example, the bridge may interject that the conference call will end in five minutes, or provide other administrative information. Similarly, the bridge may interrupt the speaker by sending a beep when someone leaves or joins the call. Additionally, on a large conference call with many participants or with unfamiliar participants, it may be difficult for people participating on the call to determine who is speaking.
Other telephone services such as call waiting also generate a beep or other audible signal that temporarily interrupts the person who is speaking, so that the listeners may be provided with a signal associated with the service. In the example of call waiting, the telephone switch may temporarily stop transmitting the voice signal from the other person on the call and generate a Beep that is interpreted by the person receiving the second call as a signal that another call is on the other line. Since the beep is transmitted instead of the normal voice signal, the person receiving the second call may lose half a second or more of the audio and may need to have the person repeat what was being said at that point in the conversation.